organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

3-(2-Pyrid­yl)-5-(4-pyrid­yl)-4-(p-tol­yl)-1H-1,2,4-triazole

aBenxi Health School of Liaoning, Liaoning 117022, People's Republic of China, and bOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China
*Correspondence e-mail: quzr@seu.edu.cn

(Received 25 April 2009; accepted 1 May 2009; online 7 May 2009)

In the mol­ecule of the title compound, C19H15N5, the dihedral angles formed by the plane of the triazole ring with those of the 2-pyridyl, 4-pyridyl and p-tolyl rings are 28.12 (10), 34.62 (10) and 71.43 (9)°, respectively. The crystal structure is consolidated by C—H⋯π hydrogen-bonding inter­actions and by ππ stacking inter­actions, with a centroid–centroid distance of 3.794 (4) Å.

Related literature

For the pharmaceutical and agricultural applications of triazoles, see: Grénman et al. (2003[Grénman, H., Salmi, T., Mäki-Arvela, P., Wärnå, J., Eränen, K., Tirronen, E. & Pehkonen, A. (2003). Org. Process Res. Dev. 7, 942-950.]). For general background on the coordination chemistry of triazoles, see: Haasnoot (2000[Haasnoot, J. G. (2000). Coord. Chem. Rev. 200-202, 131-185.]); Klingele & Brooker (2003[Klingele, M. H. & Brooker, S. (2003). Coord. Chem. Rev. 241, 119-132.]); Beckmann & Brooker (2003[Beckmann, U. & Brooker, S. (2003). Coord. Chem. Rev. 245, 17-29.]). For the synthesis of the title compound, see: Erwin (1958[Erwin, K. (1958). J. Org. Chem. 23, 1086-1087.]).

[Scheme 1]

Experimental

Crystal data
  • C19H15N5

  • Mr = 313.36

  • Monoclinic, P 21 /c

  • a = 5.6104 (11) Å

  • b = 16.312 (3) Å

  • c = 16.902 (4) Å

  • β = 105.07 (3)°

  • V = 1493.6 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Rigaku SCXmini diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.982, Tmax = 0.983

  • 13896 measured reflections

  • 2918 independent reflections

  • 1734 reflections with I > 2σ(I)

  • Rint = 0.105

Refinement
  • R[F2 > 2σ(F2)] = 0.071

  • wR(F2) = 0.159

  • S = 1.07

  • 2918 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11ACg1i 0.93 2.79 3.630 (4) 150
C12—H12ACg3 0.93 2.90 3.532 (4) 126
C14—H14ACg1ii 0.93 2.76 3.628 (4) 156
C18—H18ACg2iii 0.93 2.78 3.615 (4) 149
C19—H19CCg3iv 0.96 3.08 3.698 (4) 124
Symmetry codes: (i) [x+1, -y-{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) x+1, y, z; (iii) x-1, y, z; (iv) -x, -y, -z. Cg1, Cg2 and Cg3 are the centroids of the N1–N3/C1,C2, N4/C3–C7 and N5/C8–C12 rings, respectively.

Table 2
ππ Stacking interaction geometry

Group 1 Group 2 α (°) DCC (Å) τ (°)
Cg2 Cg2i 0.0 3.794 (3) 31.30
Symmetry code: (i) 3 − x, 1 − y, 2 − z. α is the dihedral angle between the planes, DCC is the length of the centroid–centroid vector, τ is the angle subtended by the plane normal to CC and Cg2 is the centroid of ring N5/C8–C12.

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL/PC (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information


Comment top

The main interest in triazoles lies in their pharmaceutical and agricultural applications (Grénman et al., 2003). The utilization of 1,2,4-triazole derivatives as bridging ligands in transition-metal complexes is currently of considerable interest because of the fact that it represents a hybrid of pyrazole and imidazole with regard to the arrangement of its heteroatoms, thus promising a rich and versatile coordination chemistry (Haasnoot, 2000; Klingele & Brooker, 2003; Beckmann & Brooker, 2003). We report here the crystal structure of the title compound, which is a substituted 1,2,4-triazole synthesized by the reaction of 4,4'-dimethylphenylphosphazoanilide with N-(2-pyridyl)-N'-(4-pyridyl)hydrazine in o-dichlorobenzene (Erwin, 1958).

The structure of the title compound (Fig. 1) features a dihedral angle of 28.12 (10)° between the 2-pyridyl and triazole rings, a dihedral angle of 34.62 (10)° between the 4-pyridyl and triazole rings, and a dihedral angle of 71.43 (9) ° between the p-tolyl and the triazole rings. The crystal structure is stabilized by C—H···π hydrogen interactions (Table 1) and ππ stacking interactions (Table 2).

Related literature top

For the pharmaceutical and agricultural applications of triazoles, see: Grénman et al. (2003). For a general background on the coordination chemistry of triazoles, see: Haasnoot (2000); Klingele & Brooker (2003); Beckmann & Brooker (2003). For the synthesis of the title compound, see: Erwin (1958).

Experimental top

A mixture of 4,4'-dimethylphenylphosphazoanilide (3.60 g, 14.9 mmol) and N-(2-pyridyl)-N'-(4-pyridyl)hydrazine (3.00 g, 12.4 mmol) in o-dichlorobenzene (30 ml) was refluxed for 3 h, then conc. HCl (5 ml) and H2O (5 ml) were added to the system after the removal of the solvent under reduced pressure. After refluxing for 1 h, the mixture was filtered and the fietrate was neutralized with K2CO3 to pH 8–9 to achieve a white solid. Colourless crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of an ethanol solution.

Refinement top

Positional parameters of all the H atoms were calculated geometrically and were allowed to ride on the C atoms to which they are bonded with, C—H = 0.93 Å (aromatic) or 0.96 Å (methyl), and with Uiso(H) = 1.2Ueq(Caromatic) or Uiso(H) = 1.5Ueq(Cmethyl).

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.
3-(2-Pyridyl)-5-(4-pyridyl)-4-(p-tolyl)-1H-1,2,4-triazole top
Crystal data top
C19H15N5F(000) = 656
Mr = 313.36Dx = 1.394 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1730 reflections
a = 5.6104 (11) Åθ = 3.0–27.5°
b = 16.312 (3) ŵ = 0.09 mm1
c = 16.902 (4) ÅT = 293 K
β = 105.07 (3)°Prism, colourless
V = 1493.6 (6) Å30.20 × 0.20 × 0.20 mm
Z = 4
Data collection top
Rigaku SCXmini
diffractometer
2918 independent reflections
Radiation source: fine-focus sealed tube1734 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.105
CCD_Profile_fitting scansθmax = 26.0°, θmin = 3.5°
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
h = 66
Tmin = 0.982, Tmax = 0.983k = 2020
13896 measured reflectionsl = 2020
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.071Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.159H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0527P)2 + 0.6603P]
where P = (Fo2 + 2Fc2)/3
2918 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C19H15N5V = 1493.6 (6) Å3
Mr = 313.36Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.6104 (11) ŵ = 0.09 mm1
b = 16.312 (3) ÅT = 293 K
c = 16.902 (4) Å0.20 × 0.20 × 0.20 mm
β = 105.07 (3)°
Data collection top
Rigaku SCXmini
diffractometer
2918 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
1734 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.983Rint = 0.105
13896 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0710 restraints
wR(F2) = 0.159H-atom parameters constrained
S = 1.07Δρmax = 0.32 e Å3
2918 reflectionsΔρmin = 0.26 e Å3
217 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C11.0349 (6)0.66367 (18)0.84606 (18)0.0362 (8)
C20.7141 (5)0.73132 (19)0.78095 (17)0.0349 (7)
C30.5160 (6)0.79095 (19)0.75540 (17)0.0360 (8)
C40.3738 (7)0.9211 (2)0.7518 (2)0.0508 (9)
H4B0.40040.97570.76730.061*
C50.1503 (6)0.9004 (2)0.7039 (2)0.0480 (9)
H5B0.02730.93960.68700.058*
C60.1094 (6)0.8215 (2)0.6810 (2)0.0522 (10)
H6A0.04300.80560.64780.063*
C70.2918 (6)0.7655 (2)0.70656 (19)0.0453 (8)
H7A0.26580.71080.69140.054*
C81.2577 (6)0.63716 (17)0.90639 (19)0.0346 (7)
C91.4365 (6)0.59609 (18)0.8799 (2)0.0418 (8)
H9A1.41530.58590.82430.050*
C101.6455 (6)0.5704 (2)0.9356 (2)0.0471 (9)
H10A1.76480.54280.91670.056*
C111.5079 (6)0.6215 (2)1.0397 (2)0.0455 (9)
H11A1.53030.63011.09560.055*
C121.2956 (6)0.64888 (19)0.98817 (19)0.0406 (8)
H12A1.17740.67541.00860.049*
C130.9579 (5)0.79279 (17)0.91387 (17)0.0310 (7)
C141.1613 (6)0.84102 (19)0.92208 (19)0.0407 (8)
H14A1.25390.83850.88380.049*
C151.2267 (6)0.8930 (2)0.9874 (2)0.0481 (9)
H15A1.36590.92580.99350.058*
C161.0920 (6)0.89820 (18)1.04469 (19)0.0421 (8)
C170.8873 (6)0.84945 (19)1.03423 (19)0.0429 (8)
H17A0.79300.85201.07200.052*
C180.8200 (5)0.79711 (19)0.96907 (17)0.0362 (7)
H18A0.68020.76450.96250.043*
C191.1735 (8)0.9536 (2)1.1171 (2)0.0689 (12)
H19A1.31980.98241.11380.103*
H19B1.20820.92161.16650.103*
H19C1.04500.99231.11760.103*
N10.9349 (5)0.62309 (16)0.77955 (16)0.0446 (7)
N20.7292 (5)0.66575 (17)0.73835 (16)0.0443 (7)
N30.9026 (4)0.73278 (14)0.84991 (14)0.0324 (6)
N40.5604 (5)0.86832 (16)0.77874 (16)0.0453 (7)
N51.6862 (5)0.58304 (17)1.01564 (19)0.0508 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.044 (2)0.0345 (17)0.0313 (17)0.0008 (15)0.0120 (15)0.0043 (14)
C20.0358 (18)0.0410 (18)0.0263 (16)0.0069 (14)0.0054 (14)0.0005 (15)
C30.0404 (18)0.0421 (19)0.0238 (15)0.0069 (15)0.0054 (14)0.0014 (14)
C40.056 (2)0.040 (2)0.051 (2)0.0005 (17)0.0052 (19)0.0049 (17)
C50.043 (2)0.050 (2)0.047 (2)0.0048 (17)0.0052 (17)0.0093 (17)
C60.040 (2)0.062 (3)0.047 (2)0.0066 (18)0.0017 (17)0.0049 (19)
C70.046 (2)0.0430 (19)0.0419 (19)0.0092 (16)0.0016 (16)0.0041 (16)
C80.0388 (19)0.0289 (16)0.0374 (18)0.0048 (13)0.0122 (15)0.0015 (14)
C90.049 (2)0.0355 (18)0.0425 (19)0.0032 (16)0.0153 (17)0.0008 (15)
C100.048 (2)0.0399 (19)0.059 (2)0.0016 (16)0.0227 (19)0.0037 (17)
C110.045 (2)0.047 (2)0.042 (2)0.0038 (17)0.0087 (17)0.0008 (16)
C120.0382 (19)0.047 (2)0.0371 (18)0.0025 (15)0.0114 (15)0.0003 (16)
C130.0326 (17)0.0314 (16)0.0264 (15)0.0044 (13)0.0030 (13)0.0009 (13)
C140.0410 (19)0.0423 (19)0.0382 (18)0.0073 (15)0.0094 (15)0.0019 (16)
C150.044 (2)0.0390 (19)0.055 (2)0.0101 (16)0.0024 (18)0.0039 (17)
C160.055 (2)0.0289 (17)0.0324 (18)0.0048 (16)0.0056 (17)0.0024 (14)
C170.056 (2)0.0401 (19)0.0331 (18)0.0051 (16)0.0132 (16)0.0022 (15)
C180.0342 (17)0.0413 (18)0.0317 (17)0.0066 (14)0.0060 (14)0.0033 (14)
C190.098 (3)0.045 (2)0.046 (2)0.005 (2)0.013 (2)0.0117 (18)
N10.0515 (18)0.0429 (16)0.0381 (15)0.0024 (13)0.0093 (14)0.0070 (13)
N20.0477 (17)0.0464 (16)0.0360 (15)0.0020 (14)0.0057 (13)0.0070 (14)
N30.0372 (15)0.0337 (14)0.0257 (13)0.0043 (11)0.0070 (11)0.0043 (11)
N40.0505 (18)0.0413 (16)0.0396 (16)0.0045 (14)0.0036 (14)0.0006 (13)
N50.0429 (17)0.0485 (18)0.060 (2)0.0045 (14)0.0115 (15)0.0045 (15)
Geometric parameters (Å, º) top
C1—N11.300 (4)C10—H10A0.9300
C1—N31.361 (4)C11—N51.331 (4)
C1—C81.458 (4)C11—C121.356 (4)
C2—N21.304 (4)C11—H11A0.9300
C2—N31.355 (3)C12—H12A0.9300
C2—C31.456 (4)C13—C181.360 (4)
C3—N41.326 (4)C13—C141.363 (4)
C3—C71.377 (4)C13—N31.431 (3)
C4—N41.340 (4)C14—C151.365 (4)
C4—C51.347 (4)C14—H14A0.9300
C4—H4B0.9300C15—C161.376 (5)
C5—C61.345 (5)C15—H15A0.9300
C5—H5B0.9300C16—C171.370 (5)
C6—C71.356 (5)C16—C191.494 (4)
C6—H6A0.9300C17—C181.367 (4)
C7—H7A0.9300C17—H17A0.9300
C8—C121.356 (4)C18—H18A0.9300
C8—C91.375 (4)C19—H19A0.9600
C9—C101.365 (4)C19—H19B0.9600
C9—H9A0.9300C19—H19C0.9600
C10—N51.328 (4)N1—N21.372 (4)
N1—C1—N3110.2 (3)C11—C12—H12A120.4
N1—C1—C8123.6 (3)C8—C12—H12A120.4
N3—C1—C8126.3 (3)C18—C13—C14120.7 (3)
N2—C2—N3109.9 (3)C18—C13—N3120.2 (3)
N2—C2—C3122.6 (3)C14—C13—N3118.9 (3)
N3—C2—C3127.5 (3)C13—C14—C15118.9 (3)
N4—C3—C7122.5 (3)C13—C14—H14A120.6
N4—C3—C2118.5 (3)C15—C14—H14A120.6
C7—C3—C2119.0 (3)C14—C15—C16121.7 (3)
N4—C4—C5124.5 (3)C14—C15—H15A119.1
N4—C4—H4B117.8C16—C15—H15A119.1
C5—C4—H4B117.8C17—C16—C15117.9 (3)
C6—C5—C4118.4 (3)C17—C16—C19121.6 (3)
C6—C5—H5B120.8C15—C16—C19120.4 (3)
C4—C5—H5B120.8C18—C17—C16120.9 (3)
C5—C6—C7119.6 (3)C18—C17—H17A119.6
C5—C6—H6A120.2C16—C17—H17A119.6
C7—C6—H6A120.2C13—C18—C17119.9 (3)
C6—C7—C3118.9 (3)C13—C18—H18A120.1
C6—C7—H7A120.5C17—C18—H18A120.1
C3—C7—H7A120.5C16—C19—H19A109.5
C12—C8—C9117.8 (3)C16—C19—H19B109.5
C12—C8—C1123.3 (3)H19A—C19—H19B109.5
C9—C8—C1118.8 (3)C16—C19—H19C109.5
C10—C9—C8119.5 (3)H19A—C19—H19C109.5
C10—C9—H9A120.2H19B—C19—H19C109.5
C8—C9—H9A120.2C1—N1—N2107.3 (3)
N5—C10—C9123.0 (3)C2—N2—N1107.6 (2)
N5—C10—H10A118.5C2—N3—C1104.9 (2)
C9—C10—H10A118.5C2—N3—C13129.0 (2)
N5—C11—C12124.3 (3)C1—N3—C13126.1 (2)
N5—C11—H11A117.9C3—N4—C4116.1 (3)
C12—C11—H11A117.9C10—N5—C11116.2 (3)
C11—C12—C8119.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cg1i0.932.793.630 (4)150
C12—H12A···Cg30.932.903.532 (4)126
C14—H14A···Cg1ii0.932.763.628 (4)156
C18—H18A···Cg2iii0.932.783.615 (4)149
C19—H19C···Cg3iv0.963.083.698 (4)124
Symmetry codes: (i) x+1, y3/2, z1/2; (ii) x+1, y, z; (iii) x1, y, z; (iv) x, y, z.

Experimental details

Crystal data
Chemical formulaC19H15N5
Mr313.36
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)5.6104 (11), 16.312 (3), 16.902 (4)
β (°) 105.07 (3)
V3)1493.6 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerRigaku SCXmini
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.982, 0.983
No. of measured, independent and
observed [I > 2σ(I)] reflections
13896, 2918, 1734
Rint0.105
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.071, 0.159, 1.07
No. of reflections2918
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.26

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008), PRPKAPPA (Ferguson, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cg1i0.932.793.630 (4)150.0
C12—H12A···Cg30.932.903.532 (4)125.8
C14—H14A···Cg1ii0.932.763.628 (4)155.9
C18—H18A···Cg2iii0.932.783.615 (4)149.2
C19—H19C···Cg3iv0.963.083.698 (4)123.6
Symmetry codes: (i) x+1, y3/2, z1/2; (ii) x+1, y, z; (iii) x1, y, z; (iv) x, y, z.
π-π Stacking interaction geometry (α is the dihedral angle between the planes, DCC is the length of the centroid–centroid vector, τ is the angle subtended by the plane normal to CC. Cg2 is the centroid of ring N5/C8–C12) top
Group 1Group 2α (°)DCC (Å)τ (°)
Cg2Cg2i0.03.794 (3)31.30
Symmetry code: (i) 3-x, 1-y, 2-z.
 

Acknowledgements

This work was supported by the Technical Fund Financing Projects (grant Nos. 9207042464 and 9207041482) from Southeast University to ZRQ.

References

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